421 ' Transa ctions. — Geology. 



places in the cliffs of Timaru, only four feet thick, but still exhibiting well, as 



I shall show in the sequel, the peculiar nature of these beds. This regularity 



is very striking and is of the highest importance, as it shows us, that since the 



deposition and cooling of that dolerite sheet, no disturbance, except a gradual 



slow upheaval of the country, has taken place, although other proofs are not 



wanting to demonstrate clearly that minor changes have occurred, and that 



the present configuration of the surface, near and in Timaru, is not at all in 



accordance with that which the dolerite below presents. There is no doubt 



that most of the many spurs which intersect the Timaru plateau in all 



directions, although all leading towards the sea, have been formed by the 



present surface drainage since the last silt covering was deposited." 



" I shall now proceed to give some details concerning the nature of the 



cliffs which form the Timaru roadstead, as they will assist in following the 



deductions at the end of this report, based upon the results obtained during 

 this survey. 



" The cliffs south of the landing place consist entirely of silt, forming banks 

 often 50 to 60 feet high ; but as, besides the occurrence of the dolerite in 

 Saltwater Creek (Otipua) and Pig-hunting Creek, near the sea, the Patiti Reef 

 shows these loose banks have been protected by the dolerites, which form here 

 reefs in the sea, and which have broken, and are still breaking, the force of the 

 waves and currents. After having passed the landing place, where I had an 

 opportunity of examining the silt in the new cutting, giving a vertical section 

 of about 25 feet, we reach the first bed of rocks." 



"The rock, for a thickness of about 10 to 12 feet, is here visible, and 

 consists of large blocks, being irregularly joined, which has been without 

 doubt the effect of cooling. These joints are filled with silt, often hardened 

 and ferruginous, as if it had been deposited during the cooling of the rock, so 

 that the heat had been sufficient to produce some change in it." 



" Advancing towards the north we pass to the next cliff, which consists 

 entirely of silt, being at its northern end near the lagoon about 30 feet high. 

 No fossils of any kind rewarded my search ; and only in one locality the 

 uniformity of this deposit was broken by the occurrence of a layer of white 

 fine silt of about a foot in thickness, 12 feet above the sea level, interstratified 

 with the yellow coarse silt, and having somewhat the appearance of glacier 

 mud, being almost impalpable." 



At " Pig-hunting Creek * * the dolerites are only confined to 

 its northern bank until it approaches the slopes of Mount Horrible, where 

 again the rocks are exposed on both banks. Following the dolerite sheet of 



Tims 



Hor 



thicker the more we advance towards that mountain, and, as the beautiful 



western 



